The use of class A drug crystal meth could become as problematic as crack cocaine within four years, police are warning.

The Association of Chief Police Officers (Acpo) predicts that use of the drug is rising and is comparing the growth in the UK with the pattern of use in Australia and the US, where it's reacheded epidemic levels in some areas.

So, what is crystal meth?

Crystal meth, or methyamphetamine, is a highly-addictive form of amphetamine or stimulant drug which acts on the brain and nervous system.

In its most refined form, it's crystallised so it can be smoked easily in a pipe, which are often homemade. It can also be in tablet or powder forms which can be swallowed, snorted or injected.

It's also known as ice, glass, Tina, Christine and yaba.

It is often mixed with laundry detergent and lighter fluid.

'Meth mouth' - the results of smoking crystal meth

What are the effects of crystal meth?

Users become euphoric, exhilarated and aroused. They become more mentally alert and energetic with a lack of fatigue, as well as a decrease in appetite.

The drug produces a very intense 'rush' similar to that produced by crack cocaine but lasts much longer. One small hit can affect the user for up to 16 hours.

Users often lose their sexual inhibitions which can result in dangerous unprotected sex for hours - sometimes days - on end, which increases the chance of STD and HIV infection.

Users may become obsessed with performing repetitive tasks such as cleaning, hand-washing, or assembling and disassembling objects. They can also become confused and violent.

They can experience bizarre behaviour, diarrhorea, anxiety, paranoia, excessive sweating, tremors, jaw-clenching and agitation. Prolonged use can lead to weight loss, depression, rapid tooth decay known as "meth mouth", psychosis and skin lesions.

Addiction can lead to brain damage, 'formication', which is the sensation that your skin is crawling with bugs, with may lead you to constantly pick at your flesh, causing sores and infections.

Death from overdose is usually due to stroke, heart or kidney failure, lung collapse or through the body over-heating.

After just one year one crystal meth for this addict

How long has crystal meth been around for?

It was first made at the turn of the 20th Century in chemistry laboratories in both Japan and Germany for use in medicine.

One of the earliest uses of methamphetamine was by the German military in World War II.

Chocolate laced with with methamphetamine was given to pilots.

From 1942 until his death in 1945, Adolf Hitler was given daily intravenous injections of methamphetamine by his personal physician as a treatment for depression and fatigue.

How widespread is it in the UK?

There are no official figures on the number of crystal meth users in Britain. Police describe it as still being a relatively "minor problem".

The charity Drugscope estimate that there are 100 000 crack cocaine users in the UK, the number of people currently using crystal meth is a fraction of that.

Is it still used legally?

In some parts of the world, drugs including a form of methamphetamine are used to treat obesity, narcolepsy and attention deficit hyperactivity disorder.

Highly-addictive and deadly manufactured crystal meth granules

How much does crystal meth cost on the street?

Half a gram is currently around £25 or one hit on the street is around £15.

What happens if you get caught with crystal meth?

As a Class A drug, it is illegal to have, give away or sell. Possession can get you up to seven years in jail and/or an unlimited fine. However, supplying someone else, even your friends, can get you life imprisonment and/or an unlimited fine.